[Beowulf] Home beowulf - NIC latencies

[Andrew Piskorski]

On Thu, Feb 03, 2005 at 04:53:27AM +0100, Vincent Diepeveen wrote:

> Please note MPI is probably what i'll use, though i keep finding
> online information about 'gamma'. Is that faster latency than MPI
> implementations?

  http://www.disi.unige.it/project/gamma/

Gamma is a non-TCP/IP Linux 2.6.x network driver for Intel Pro/1000
gigabit ethernet cards, for use with MPI.  It offers much better
latency (11 us or so) than TCP/IP over ethernet (maybe 60 or 100 us),
but worse than the specialized HPC interconnects (maybe 3 us).

The attraction of GAMMA, is that Intel Pro/1000 cards can be had for
$11 to $60 or so each (depending on exact model, etc.), and gigabit
switches are also pretty cheap, while SCI or Myrinet is somewhere in
the $500 to $1500 per node range (I don't keep track).

So if your application can benefit from lower latency, but you want
something really cheap, GAMMA should be well worth trying.

-- 
Andrew Piskorski <atp at piskorski.com>
http://www.piskorski.com/